Can someone help me? I was surfing the web when suddenly a page came up that told me my computer was being attacked by trojans (about 364 of them) It freaked me out. Then it popped up loads of things asking me to install stuff. I tried to close it down as quickly as possible

I have Norton Security on my PC and I am running a scan now, now if I have worms will it detect them and kill them? or is all my data under attack?

My history page logs the page as:
http://antimalwareliveproscanv3.com/1/?id=2009-1568&smersh=9fc485845&back=%3DTQ12zDxNMQNMI%3DO